The present invention relates to vertical filing systems and more particularly to an improved vertical filing system which is easy to manufacture, inexpensive, and versatile in its use as a storage system as well as a transportation system.
Typical vertical files include a retaining device attached to sheet material and a frame. Examples of vertical files are shown in U.S. Pat. Nos. 1,135,310 and 1,165,108 issued to Memmler, U.S. Pat. No. 1,911,277 issued to Helmer, U.S. Pat. No. 3,298,374 issued to Grundell, and U.S. Pat. No. 4,658,966 issued to Broek. Each of these patents shows a different method of holding large sheets of material, such as blueprints, newspapers, maps, etc. in a vertical filing arrangement.
The Memmler U.S. Pat. Nos. 1,135,310 and 1,165,108, are track systems which use binder clips to hold the sheet material. The binder clips, shown in FIGS. 3 and 4, are opened by manually squeezing ears 21 together to open clamping portion 17. Material is inserted into the clamping portions such that the free edges of the clamping portions engage the sheet material to hold it in place. The binder clip has grooves 15 to receive and engage inwardly extending flanges 11 on guides 10. Guides 10 are mounted to a carrier frame shown generally at 8. In this way, the sheet material can be clamped by the binder clamp and then slid onto and off of the carrier frame.
Helmer U.S. Pat. No. 1,911,277, uses a manual tensioning means to further enhance the biasing of the binder clip. The clip is fairly complex and includes a cam to enhance its gripping action. The cam is adjusted by nut 25. The clip is received within rails 34 which accommodate a conical section 38 at the top of the clips.
A further type of system is taught by U.S. Pat. No. 4,658,966 which employs a clip that utilizes a binder strip 31 having sides 41 and 42 which resiliently bias tightly against one another to clampingly retain sheets of material. Strip 31 can be used in conjunction with coupling means 112 as shown in FIGS. 4 and 5 to hang groups of sheet material. The binder strip 31 has means for mounting it to a laterally extending rod 27 and pins 79.
U.S. Pat. No. 3,298,374 shows a still further type of vertical filing system which uses button-type fasteners 11 which pass through holes in the flanges 9 as well as through the papers 10. The flange 9 is mounted within a channel bar member 1 which is in turn mounted to a support frame.
Each of the above vertical filing systems has disadvantages. The binder clip type are costly to manufacture and rely upon the bias of the binder clip to ensure proper retention. As the biasing force is increased to ensure greater retention, the difficulty in opening the binder clip increases proportionately.
The mechanical spring type is complicated in its construction and expensive to manufacture. It overcomes the disadvantage of the binder clip type but at greater expense. Also, the mechanical spring adjustment type does not permit the sheets of material to be easily rolled upon the mounting clip which could be done by the unit disclosed in the Memmler patents, '108 and '310.
The filing system taught by Grundell, '374, has the disadvantage of drilling a hole through the sheet material for the button fastener. This is time-consuming and also destroys the integrity of the sheet material which may be undesirable. Additionally, the ability to roll the sheet material onto the clip is difficult.
Lastly, the Broek patent, '966, has difficulties similar to those encountered in the binder clip vertical filing systems. The amount of tension is determined by the binder strip 31. This cannot be adjusted, and therefore the user is left with a single biasing force. Unlike the binder clip, there is no easy way to separate the legs of the binder strip 31 to insert sheets of material or coupling means 112.